Sky in Italy says that the Forest are close to signing Houssem Aouar.
Aouar has less than a year left on his current contract with Lyon.
A move to Real Betis collapsed recently, and he has been linked with a move to a number of English clubs.
Forest have signed more than a dozen players so far this summer, with the most recent signing being Cheikhou Kouyate, who joined on a two-year contract.
Forest's 14th signing of the summer was a free agent after he left Palace at the end of the 2020-21 season.
The signing of Dennis was done on Saturday.
He scored 10 goals for the Hornets last season, but they were not good enough to stay up.
Dennis wasn't in the squad for Friday night's win over Burnley as he finalized his move to the City Ground.
The transfer window will close at 11pm on September 1st.
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